Keane, who has successful moved from right-back to star in midfield over recently weeks and impressed once more in completing 90 minutes of Tuesday night's 2-0 win over Oldham.
But with surgery definitely required in the near future, Grayson would rather the operation takes place sooner rather that later to give the former Luton man as full a pre-season as possible.
"He's seen a specialist this week so if he gets a slot in the next few days or next week then he'll go in and have it done, so we'll see where we are," he said.
"It's possible (Oldham could have been his last game of the season) but knowing him he'll want to soldier on, but there's probably no point in respect of the time span it takes for a groin to settle down over the summer.
"We might as well get it done and then he he's ready for pre-season."